A memory apparatus shaped like a card or a stick (hereinafter referred to as memory card is used as a recording medium in personal computers and digital still cameras. The memory card has a flash memory that is used as memory means.
The memory card has a storage area, which is divided into a plurality of blocks. The data written into the flash memory used as memory means is managed in units of blocks. These blocks may be roughly classified into system blocks and user blocks. A system block stores read-only data. System-related data, such as data representing the block configuration, is written as the read-only data into the system block before the memory card is delivered from the factory. A user block stores user data.
The data items recorded in the memory card may include ones that should not be easily rewritten or read out by the user. Among such data items are the password and the use history. (Hereinafter, data items of this type shall be generally called “special data”. In the conventional memory card, special data is stored in the user block, too.
There arise no problems if the special data is stored in the user block, provided that the memory card is used in an electronic apparatus so designed that ordinary users cannot make an access to the special data. If the memory card is used in a general-purpose data-processing electronic apparatus, such as a personal computer, however, ordinary users can easily access the user block. This is because the entire user block can be usually accessed. Inevitably, the contents of the special data are easily made known to the ordinary users or may be easily rewritten.